<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
    <title>css外层DIV半透明内层div不透明-弹出层效果的实现【实例】</title>
    <style type="text/css">
        <!--
        body, td, th {
            font-size: 12px;
            padding: 0;
            margin: 0;
        }

        .tanchuang_wrap {
            /*width: 600px;*/
            height: 400px;
            position: absolute;
            left: 0px;
            top: 0px;
            z-index: 100;
            display: none;
        }

        .lightbox {
            width: 100%;
            z-index: 101;
            height: 100%;
            background-color: red;
            filter: alpha(Opacity=20);
            -moz-opacity: 0.2;
            opacity: 0.2;
            position: fixed;
            top: 0px;
            left: 0px;
        }

        .tanchuang_neirong {
            width: 30%;
            margin: 0 30%;
            height: 153px;
            border: solid 1px #f7dd8c;
            background-color: #FFF;
            position: fixed;
            z-index: 105;
            left: 123px;
            top: 123px;
        }

        -->
    </style>
    <script language="javascript">
        function closeDiv(divId) {
            document.getElementById(divId).style.display = 'none';
        }
        function displayDiv(divId) {
            document.getElementById(divId).style.display = 'block';
        }
    </script>
</head>
<body>
<div style="width:100%; height:400px; position:relative; text-align:center;">
    <div class="tanchuang_wrap" id="aaaa">
        <div class="lightbox"></div>
        <div class="tanchuang_neirong">
            <p><span onClick="closeDiv('aaaa')"
                     style=" cursor:pointer;">关闭</span></p>
            这里是弹窗内容
        </div>
    </div>
    <span onclick="displayDiv('aaaa')" style="cursor:pointer;">点击我</span>
    <p>测试通过，兼容IE6.0、IE7.0、火狐3.6、遨游等各大浏览器</p>
</div>
</body>
</html>